Fragmentation

Fragmentation occurs in operating systems where files over a specific size are stored as fragments rather than one continuos sequence of bits in a storage medium. This process allows the free sections of the storage medium to be used for other purposes. For example, in the Windows 95 operating system, files are fragmented and stored in a FAT (file allocation table) to preserve space on the hard drive. Over time, fragmentation can slow down the process of accessing data. For this reason, a user may be required to use a defragmenter utility to efficiently reorganize the data in a storage medium. This process is known as defragmentation. In regard to TCP/IP (Transmission Control Protocol/Internet Protocol), fragmentation is defined as the process of breaking packets into the smallest possible PDU (packet data unit) supported by the underlying networks. In the OSI (Open Systems Interconnection) model, this process is called segmentation.